#!/usr/bin/env python
# -*- coding: utf-8 -*-
#===============================================================================
# Copyright 2011 zod.yslin
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# 
# Author: zod.yslin
# Email: 
# File Name: exception.py
# Description: 
# 
# Edit History: 
#   2011-08-09    File created.
#===============================================================================
class B:
    pass
class C(B):
    pass
class D(C):
    pass

"""
raise Class, instance
raise instance
    instance must be an instance of Class or of a class derived from it
raise instance.__class__, instance
    A class in an except clause is compatible with an exception if it is 
    the same class or a base class thereof (but not the other way around — 
    an except clause listing a derived class is not compatible with a base class). 
"""

for c in [B, C, D]:
    try:
        raise c()
    except D:
        print "D"
    except C:
        print "C"
    except B:
        print "B"
